In the middle of Idaho’s Lost River desert is a green street sign that reads “Atomic City” with an arrow pointing to a lonely gravel track. One evening, some years back, I followed it. As purplish storm clouds swallowed the sun, I came across a cluster of scraggly trees and weather-beaten trailer homes. Beside an abandoned speedway sat an antiquated ambulance and across the street a neon Bar sign twinkled in the dusk. Inside the bar, I met drifter lovers from Colorado and a potbellied man in a hunting cap who worked as a spent-fuel handler for the nearby Idaho National Laboratory. We discussed nuclear energy, of which he was, not surprisingly, a fan. Then I asked the question that had brought me to Atomic City: What caused the 1961 nuclear disaster?

The spent-fuel handler ordered a shot of Jägermeister. “Have you heard of the love triangle?” he asked. I hadn’t. All I knew was there was something fishy about the disaster. Earlier that day, when I tried bringing it up at Pickle’s Place, in Arco, Idaho, thirty miles away, I received cold stares. “You won’t find much on that,” a brawny man with a girl at his side told me as he exited the restaurant. I heard the same thing at the gas station next door, and at the fleabag motel I checked into. People aggressively knew nothing, which seemed to imply there was something to know.

“One guy’s wife was messing around with another guy,” said the fuel handler, after downing his Jäger. “He got pissed off and messed up…I shit you not.” He then reenacted how the disaster might have happened: “You fuck my wife, I fuck you up” — and with fingers clenched he yanked his hand upward, making the motion of pulling a control rod out of a reactor core. Boom.

***

At 9:01 p.m., on January 3, 1961, a nuclear reactor the size of a small grain silo exploded in the Lost River desert. All three men inside the Stationary Low-Power Plant Number 1, or SL-1, were killed. To this day, they are among the only recorded nuclear fatalities ever to occur on U.S. soil. Even in the wake of Japan’s Fukushima nuclear meltdown, in March 2011, no one in the mainstream media mentioned the SL-1 disaster. The tsunami that caused Japan’s meltdown was viewed as something unpredictable, a result of poorly understood plate tectonics and mercurial seas, while the meltdown itself was perceived otherwise. It could have been prevented, said experts, with better safety protocols. Had anyone remembered SL-1, perhaps the conversation would have been different.

Few Americans know their nation’s nuclear history. In 1946, after the bombing of Hiroshima showed that the atom could destroy a city, Congress created the Atomic Energy Commission to show it could also generate electricity. Reactors sprang from the sage of the Lost River desert, a spot chosen because it was sparsely populated, geologically stable and arid, but with good access to water and electricity. The site was called the National Reactor Testing Station. On December 20, 1951, the Experimental Breeder Reactor 1 powered four lightbulbs, the world’s first nuclear energy. Four years later, Arco became the world’s first town powered by nuclear energy. Businesses, thinking radiation would remove impurities from or enhance the strength of their products, blasted their goods — gold, diamonds, plastic, papayas, potatoes — with gamma rays.

The fuel of the future had arrived, and it would run cities, make materials stronger and food imperishable, and protect the nation by powering the Distant Early Warning Line, a ring of remote Arctic bases intended to detect America-bound Soviet missiles speeding over the ice cap. The army envisioned simple reactors that could be airlifted north in pieces, assembled like Erector Sets, and operated by regular army guys. They would train at SL-1.

The testing station was like a nuclear playground where each branch of the military pursued its own pie-in-the-sky projects. Machines were built before physicists could prove the principles to make them run. Some projects succeeded, such as the first nuclear-powered submarine, tested in a vat of water in the Idaho desert in March 1953. Others failed miserably. The air force spent more than one billion dollars trying to create a nuclear-powered aircraft. The result was a 600,000-pound plane that spewed radiation into the sky and poisoned its pilots’ internal organs. There were other mishaps, including a string of accidental meltdowns — and several triggered intentionally, to see what would happen.

SL-1 was housed in a three-story metal silo and surrounded by administration buildings slapped together with surplus war materials. It looked more like an idle granary than an endeavor to salvage humanity. And there were problems. The boron that lined the uranium fuel plates and stabilized reactions was flaking off at an unknown rate, and the control rods that regulated reactions had been sticking. Lifting the rods allowed neutrons to buzz freely and a reaction to occur, while dropping them squelched a reaction. When the rods stuck, the lifting and lowering had to be done by hand. The facility had been slated to receive a new reactor core in the spring of 1961, something the explosion prevented from happening, and thus the original core, which had a curious design, was still in use. At most reactors, several control rods must be removed to initiate a reaction, but at SL-1, pulling just the central control rod was enough. This design had never been used before, and has never been used since.

Flawed as SL-1 was, those who worked there still felt part of some epic mission. “The spirit of patriotism was absolutely palpable,” says Susan Stacy, author of a book written for the government titled Proving the Principle — A History of the Idaho National Engineering and Environmental Laboratory, 1949-1999. “I think there was a great deal of idealism about the potential for nuclear energy, this fissioning atom, to solve many of the world’s energy problems.” Young men flocked to the budding industry; Jack Byrnes and Dick Legg, two of the three workers in SL-1 the night it blew, among them.

Byrnes, a handsome twenty-year-old from Utica, New York, had joined the army at seventeen and by nineteen had married his high school sweetheart, Arlene, and become a father. After a yearlong course in reactor operations, he was assigned to SL-1. In October of 1959, he and Arlene strapped a trunk to the top of a black Oldsmobile and headed cross-country, their son, Jacky, belted between boxes in back.

Dick Legg, a stocky twenty-five-year-old from rural Michigan, had worked two years as a navy electrician before enrolling in the same nuclear course as Byrnes. He was also assigned to SL-1. Unlike Byrnes, Legg came west without a woman. (“I’ve got it all figured out with these gals,” he once told a navy friend, explaining his pickup strategy: ask every girl at the bar for a drink until one says yes, then tell her you know a spot nearby with a good band but instead drive to a drugstore and buy condoms.) In Idaho, Legg married a teenage testing-station stenographer named Judith Cole.

We know the details of these men’s lives from reports made by an AEC special investigator named Leo Miazga. The reports were later dug up by journalist William McKeown and woven into his comprehensive book, Idaho Falls: The Untold Story of America’s First Nuclear Accident, published in 2003. Miazga meanders in his analysis but his takeaway is simple enough: both Byrnes and Legg were screwups. Byrnes ignored his family, catted with strippers, and threw temper tantrums at work in which he chucked tools. Legg was unprofessional and lazy. For a gag, he once turned off a fan that cooled critical instruments, and on at least one occasion he was found sleeping in his car in the parking lot when he should have been overseeing the reactor. After Legg fudged the time card of a friend playing hooky, the friend was transferred and Byrnes brought in to fill his spot. The two had never worked together, but they had a volatile history.

One night the previous May, the SL-1 boys had gotten drunk at a strip club called the Boiler Room. Byrnes introduced to the group a chatty prostitute named Mitzi. She joined the men at a sergeant’s house for tequila and whiskey, offering sex for twenty dollars. The men talked her down to two, and Byrnes took her into a back bedroom. Afterward, Legg started a fight with him. No one quite knows why, but the sergeant who broke it up later told investigators that Legg was either scolding Byrnes for being unfaithful or razzing him about his stamina. McKeown mentions another possibility, gleaned from Miazga: Byrnes was sleeping with Legg’s wife.

On January 3, at 4:00 p.m., Byrnes and Legg began their shift. Assisting them was a trainee named Richard McKinley. The crew’s first task was to reconnect the control rods to the drive rack that moved them up and down. This required manually lifting the hundred-pound rods about four inches. Lifting the rods too far — another ten inches — would trigger a reaction, but Byrnes and Legg knew the risks. At 5:00 p.m., a patrolman stopped by, saw the men were busy, and moved on. Around 7:00 p.m., the testing-station operator placed a call to the control room. It was Byrnes’s wife, Arlene. They spoke briefly, deciding to end their marriage. According to Miazga, and relayed by McKeown, an unidentified woman tried calling back several times over the next few hours but never got through.

We don’t know Byrnes’s response to this devastating phone call. However, we do know what happened next. And from the autopsy report, we know that the man standing directly over the central control rod was Jack Byrnes.

***

At 9:01 p.m., SL-1 exploded. “When the reactor went critical, it released so much heat energy in four milliseconds that it flashed the water surrounding the fuel to steam,” reads Stacy’s book. “[Water] slammed against the lid of the pressure vessel at a velocity of 160 feet per second and 10,000 pounds per square inch exactly as if it were a piston — a water hammer. The entire vessel jumped nine feet into the air, hit the ceiling, and thumped back into place…The violence of the explosion killed all three of the men.”

McKinley was struck in the head by a piece of radioactive shrapnel that tore off half his face. Byrnes was thrown into concrete blocks, breaking ribs that pierced his heart. Legg was skewered in the gut by a flying control rod that launched him thirteen feet in the air and pinned him to the ceiling. (It took a week to get him down, requiring a pole with a hook to push him into a net attached to a crane operated by a man shielded in lead.) The men’s bodies were wrapped in several hundred pounds of lead, placed in steel coffins, and buried under a foot of concrete.

The day after I visited Atomic City, I drove east across the Lost River desert, to Idaho Falls. On a Barnes & Noble display table, I found McKeown’s book, which even looks haunting — its cover is a grainy close-up photo of a gas mask. He builds a careful case, showing that Byrnes likely caused the accident by intentionally pulling out the critical central control rod. Maybe, says McKeown, “roiled with emotion: anger, remorse, guilt, feelings of persecution…[Byrnes] wanted to do something to get Arlene’s sympathy, or just to ‘show her.’”

McKeown considers the love triangle theory, but he also reveals just how weak the evidence for it is. The fodder comes from a conversation Miazga had with an SL-1 supervisor who, in referring to Legg’s wife’s relationship with Byrnes, had used the title Miss and not Mrs. Was the supervisor subtly implying she had slept with Byrnes before being married to Legg? This seems like a great leap, but it was interpreted that way and has since become lore. To me, the love triangle theory is off the mark. The version told by the spent-fuel handler in Atomic City implies that Legg pulled the control rod to get back at Byrnes for sleeping with his wife, but regardless of who may have slept with whom, we know Byrnes pulled the control rod, not Legg. He could have pulled it in an act of rage directed at Legg, though I think it was more about Arlene and, as McKeown suggests, remorse. We are mercurial creatures, and Byrnes was known to be especially volatile. That a man with a heavy heart could pull a one-hundred-pound control rod out of a reactor core seems perfectly plausible.

Much of McKeown’s book is based on interviews he conducted in 2000 and 2001. Since then, many of the interviewees have moved or died, but I connected with one, C. Wayne Bills, the testing station’s deputy director of health and safety at the time of the accident. At the time of my visit, in April 2012, Bills was 87 and lived in a brick house in a quiet east Idaho Falls neighborhood. He was broad-shouldered, sturdy, and sharp. He grew up on a Colorado ranch and studied engineering at the University of Colorado Boulder. After graduation, he took a position testing plutonium at Los Alamos National Laboratory, in New Mexico, where the first atomic bomb was developed. It was a riveting experience. “The guy who worked across the hall from me was on the Enola Gay,” said Bills.

At Los Alamos, he met his wife, who worked in a lab that tested urine samples. After stints at an oil company in Tulsa and a glue factory in St. Louis, Bills returned to nuclear energy, taking a safety inspector job with the Atomic Energy Commission, first in Richland, Washington, and later in Idaho Falls. The place was buzzing, but in a different way than Los Alamos — more bravado than brains.

When SL-1 blew, Bills was at choir practice in Idaho Falls. He jumped into his government Studebaker, picked up an AEC doctor, and raced to the site. Near SL-1, they came across an ambulance on its way to the hospital. “I opened the door and was reading four hundred roentgens,” Bills said. The man inside was McKinley, mutilated and glowing with radiation, but somehow, until a few moments earlier, still alive. Bills turned the ambulance around. “If you go to the hospital, you contaminate everyone,” he said. His good judgment was noted, and the higher-ups chose him to lead a technical committee charged with determining exactly how the accident had happened.

***

Bills’s team showed the explosion had not been caused by SL-1’s laundry list of preexisting problems, as some experts had speculated, nor had it been caused by someone accidentally pulling the central control rod out of the core while reattaching it to the drive rack. A piece of piping used in reattaching the rod provided the critical evidence. It had been deformed by the explosion but still contained a bit of the rack to which the rod was to be attached — meaning, Legg and Byrnes had already finished attaching the rod by the time the explosion happened. Scratches on the outside of the rod indicated that it had been forcefully yanked not just fourteen inches, the distance needed to initiate a reaction, but twenty inches, the maximum distance possible.

The team tested scenarios to see whether the rod had been yanked by accident. Bills had men take turns trying to pull a hundred-pound rod upward while others held it down, then suddenly let go. Most men pulled the rod a few inches. None came close to twenty. They even looked at whether goosing could have caused a man to pull the rod out, meaning, if another man stealthily approached and poked him in the butt. Still, no one jerked hard enough to lift the rod twenty inches.

Toward the end of my conversation with Bills, after his collection of grandfather clocks had chimed several times and afternoon sunlight had begun to creep across the carpet, his wife, June, the same woman he had met in Los Alamos sixty years ago, returned from a church meeting. I began to see Bills as a classic sort of 1950s American hero, devoted to his wife, devout in his faith, dedicated to his country. In contrast, Byrnes and Legg seemed to have been bawdy, bumbling young men who were in way over their heads. Bills was passionate about nuclear energy; Byrnes and Legg had simply gone west for jobs. “These people weren’t scientists,” said Bills. “They were essentially military people; they knew how to run reactors but weren’t involved in knowing an awful lot about how they worked.”

SL-1 was a very American nuclear accident, with its high drama and focus on the individual. Fukushima, which involved protocol problems and collective blame, was a very Japanese one. But whereas Japan has been forced to confront its nuclear errors, America still marches forward, thinking Three Mile Island was its biggest nuclear mishap. The bartender in Atomic City, a weatherworn man who grew up in Alaska and spent his career fighting oil spills in the Persian Gulf, didn’t think this would change anytime soon. “This is a subject you’ll get nowhere with,” he said, as he sent me on my way, giving me an Alaskan lager for the road. “This is their black eye. As far as the industry goes, in the United States, there has never been a fatal nuclear accident.”

***

An earlier version of this story said SL-1 was the only fatal nuclear accident ever to occur in the US but several good readers have pointed out this is not the case. In May 1946, a Canadian physicist named Louis Slotin suffered a fatal injury while doing an experiment involving plutonium at a secret government laboratory outside Los Alamos, New Mexico,(Haroutune Krikor Daghlian Jr. died in 1945 after irradiating himself during a critical mass experiment at the same facility)and in July 1964, a fatal criticality accident occurred at the Wood River Junction nuclear facility, in Rhode Island. There may well have been others.

***

“Atomic City” originally appeared in the Spring 2012 issue of Tin House, “Weird Science.” Our thanks to Cheston Knapp and the Tin House staff for making this reprint possible.

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